Page 1 of 1

Gearbox oil

PostPosted: Sun May 04, 2014 10:36 am
by swiss tone
I am just doing some fluid changes.

Anyone used the millers GL5 75w90 in the gearbox/front diff? Auto data says to use that but just want to know if that's correct really. Bit of a sod apparently filling back up through the dipstick I'm told, special tool avbl might be worth getting.

I have Motul 90PA for the rear diff as some posts suggest and 5w30 synthetic for engine oils with a subaru black oil filter.

Re: Gearbox oil

PostPosted: Sun May 04, 2014 4:51 pm
by Gary75
swiss tone wrote:I am just doing some fluid changes.

Anyone used the millers GL5 75w90 in the gearbox/front diff? Auto data says to use that but just want to know if that's correct really. Bit of a sod apparently filling back up through the dipstick I'm told, special tool avbl might be worth getting.

I have Motul 90PA for the rear diff as some posts suggest and 5w30 synthetic for engine oils with a subaru black oil filter.


GL5 75/90 for front gearbox / diff, use a length of hose cut to size or long funnel to fill, no special tool required :thumb: Motul 90pa rear diff,spot on. I'm back using 5w40 Fuchs Titan with blue filter.

Re: Gearbox oil

PostPosted: Wed May 07, 2014 4:51 pm
by swiss tone
Cheers Gary, garage doing it on fri :)

Good tip on filling gearbox though!

Re: Gearbox oil

PostPosted: Wed May 07, 2014 4:52 pm
by swiss tone
Cheers Gary, garage doing it on fri :)

Good tip on filling gearbox though!

Re: Gearbox oil

PostPosted: Mon May 12, 2014 5:55 pm
by swiss tone
All oils done :D

Re: Gearbox oil

PostPosted: Fri May 30, 2014 5:14 pm
by swiss tone
I am bewildered as sick of hearing conflicting advice! Just had my one mot'd. Guy claims to be a bit of and expert with LSD diff's.
Passed with no advisories as expected after the amount of money I constantly throw at it but he said, what oils have I got in gearbox/diff and rear diff?

I told him only just changed the oils and millers GL5 75/90 in gearbox and Motul 90PA LSD oil in diff as most on here also suggest.

He said , god no, way too thick!!!! With car wheels off the ground, he turned wheels independently and said they were too stiff and thinner oil sorts it on these. He said what Subaru recommend is wrong!!!

Is he talking utter crap?? Anyone else run with thinner oil? :wtf:

Re: Gearbox oil

PostPosted: Sat May 31, 2014 8:58 pm
by Gary75
swiss tone wrote:I am bewildered as sick of hearing conflicting advice! Just had my one mot'd. Guy claims to be a bit of and expert with LSD diff's.
Passed with no advisories as expected after the amount of money I constantly throw at it but he said, what oils have I got in gearbox/diff and rear diff?

I told him only just changed the oils and millers GL5 75/90 in gearbox and Motul 90PA LSD oil in diff as most on here also suggest. :thumb:

He said , god no, way too thick!!!! With car wheels off the ground, he turned wheels independently and said they were too stiff and thinner oil sorts it on these. He said what Subaru recommend is wrong!!!

Is he talking utter crap?? Anyone else run with thinner oil? :wtf:


You have the right oils in the right places...

Is this guy for real... :cuckoo: you will have resistance from all wheels, they are connected to hubs, drive shafts / prop shafts...diffs and a gearbox.

So your guy claims he is somewhat of an expert on LSD diffs and Subaru's recommendations are wrong? What oil would he use or recommend in the gearbox and rear diff :?:

Re: Gearbox oil

PostPosted: Mon Jun 02, 2014 7:57 am
by swiss tone
I didn't warm to the guy. He said he will find out so I'm going to call in just to see what he says for the laugh element as it's only at the end of my road.

I'm with you on this one and too many people claiming to be so called experts. They do more harm than good as people actually listen to them and end up causing more problems. They should go back to greasing Fiesta's! lol :wink:

Re: Gearbox oil

PostPosted: Sat Jun 07, 2014 7:43 am
by asperformance
90PA is perfectly fine in the rear diff of an STi although probably a little over kill for a road car...........would more normally use 75w90 or 80w90 LSDS specific offerings from Millers / Motul

as for the engine i wouldn't personally use a 5-30w and would suggest a 5w40 min